Dental instrument



Dec. 2,1930. T. K. M KENZIE DENTAL INSTRUMENT Filed June 19, 1929 w a n v n m m R lll l llllllll Patented Dec. 2, 1930 THOMAS K. MCKENZIE, or nannrsoivvrrrr n, vussounf DENTAL INSTRUMENT Application filed June is,

vide means wherebythe plugger point may be readily and easily removed or replaced. With the foregoing and other objects in view, which will appear as the descriptlon proceeds, the invention resides in the combination and arrangement of parts and in the details of' construction hereinafter described and claimed, it being understood that changes in the precise embodiment of theinvention herein disclosed, may be made within the scope of what is claimed, without departing from the spirit of the invention.

Referring to the drawing: 7

Figure 1 is a side elevational view of a plugger constructed in accordance with the invention.

Figure 2 is a fragmental bottom plan view thereof.

Figure 3 is a top plan view of one end of the plugger.

Figure 4 is a sectional view through one end of the plugger.

Figure 5 is a sectional view taken on line 5-5 of Figure 4.

Figure 6 is a sectional view taken on llne 6-6 of Figure 4.

Figure 7 is a sectional view taken on'lme 7--7 of Figure 4.

Referring to the drawing in detail, the plugger comprises a body portion 5 which is provided with a' handle or grip 6 arranged intermediate the ends thereof so that either end of the instrument may be used by gripping the handle 6. The ends of the body portion 5 are beveled in opposite directions, the beveled surfaces being grooved to receive the shanks of the plugger points 7.

Secured to the body portion adjacent to each end thereof is a bar 8 which is provided 1929. Serial ire/372,146. f

the beveled end of the body portion 5, with which the bar is associated, to contact'with the plugger point to hold the plugger'point in position on the body portion.

The bar 8 at each end of the body portion is'formed withan inwardly extended finger 10 that is positioned in an opening formed in the body portion so that twisting of the bar with respect to the body portion, is absolutely prevented at all times.

Screws 11 are provided for holding the bars 8 in position on the body portion, the screws 11 passing throughopenings in the bars 8, the'threaded ends thereof passing into threaded openings formed inthe body por tion. The bars 8 are formed with gradua tions 12 with which the adjusting collars 13 that move thereover, cooperate so that the collars 13 may be moved to various positions of adjustment, with accuracy.

The 'reference' character 14 designates spring arms which are secured 'to the body portion adjacent to the ends thereof, the spring arms {having 7 their free ends overlying the upper ends of the plugger points, as clearly shown by the drawing, to the end that pressure is exerted on the plugger points, and that by adjusting the collars 13, the spring arms may he placed under various degrees of tension.

A roller 15 is carried at the upper end of each plunger point and rolls over the spring arms associated therewith, when the plugger point moves within the groove in which it is positioned. Shoulders 16 are formed on each plugger point and are adapted to contact with theunderside of the body portion 5 to restrict movement of the plugger point.

' From the foregoing it will be obvious that a person using the instrument, may adjust the spring to exert a predetermined amount of pressure on the plugger so that a tooth may be plugged under a predetermined amount of pressure, it being obvious that when the maximum amount of pressure for which the spring has been set has been applied to the instrument, the shoulders will contact with the body portion, indicating to Fwith a right angled end portion Qoverlying the operator that he is operating with the maximum amount of pressure.

A. set screw 17 extends through each collar and contacts With the body portion so that the collar may be held in its positions of adjustment.

While I have described in detail theconstruction of one end of the plugger, it is to be understood that the ends of the plugger are identical.

I claim:

1. A dental instrument including a body portion having a beveled end formed with a groove, a bar secured to the body portion and having a right angled extremity overlying the groove, a slidable plugger point positioned in the groove and held in the groove by the right angled end of the bar, means for restricting movement of the plugger point, and means for exerting pressure on the plugger point.

2. A dental instrument including a body portion, a plugger point slidably mounted at one end of the body portion, said plugger point having shoulders to engage the body portion to restrict movement of the plugger point, a spring finger mounted on the body portion, one end of the spring finger contacting with the plugger point to exert a pressure on the plugger point, and means operating over the spring finger for regulating the tension of the spring finger.

3. A dental instrument including a body portion, a slidable plugger point mounted at one end of the body portion, a spring finger mounted 011 the body portion and engaging the plugger point to exert pressure thereon, and a collar slidably mounted on the body portion and engaging the spring arm to adjust the tension of the spring arm.

In testimony that I claim the foregoing as my own, I have hereto afiixed my signature.

THOMAS K. MoKENZIE. 

